rutgerv

Hi TK, thanks for the quick reply. I can understand the way you interpret the sustain pedal, however I don't think notes should keep on playing if neither a key nor the pedal is pressed. In my explanation I forgot point 7. 'Release the sustain pedal'. And after that the note should stop, but it doesn't (!). Can you reproduce that too? Greetings, Rutger

Hi TK, I found a tiny little bit of strange behavior in the latest release: a note that hangs after a certain chain of events. I'll try to describe what I did and I hope that you can reproduce what's happend 1. Select Patch 7 (Simple Pulse) 2. Press and hold the sustain-pedal 3. Play a note and hold the key down 4. Play a second note and hold the key down (the pitch changes to this last note played) 5. Release the second note (but keep holding the first) 6. Release the first note The strange things happen here: A. When the second note is released (step 5) I would expect the pitch to return to the first note. However, it does not. Instead it stays on the pitch of the second note. I don't think that the sustainpedal usually does this with other synths. B. After step 6 the second note still hangs, while I don't touch any of the keyboard controls. I don't think that's a good idea. Can you reproduce this? I hope you can. Greetings, Rutger

Hehe, cool. I didn't know such a thing already existed. I was justed being silly. @Wilba: That's an interesting idea. It would certainly be nice to take a look at the MIOS Studio source code. But I think that merging them together may be a little too much? And another thing is that not every MIOS Studio user owns an MBSID. But it will definitely save time to use some of the classes from MIOS Studio for controlling and routing the MIDI in/out, etc. Greetings, Rutger

Alright then, Java it is :). I hope I'll get used to the syntax quickly. I've used Java before, but in the past few years I mostly used Matlab so I might need some time adjusting to Java. Greetings, Rutger

Hehe, no, I have a better idea :). Let's make a website that allows to listen to (audio) and look at (webcam) your MBSID V2 in real time! Users can upload MIDI files in a playlist that will be played on your MBSID ;). That would be a totaly cool new approach to working with hardware synths by the way. To not buy a synth but buy some 'online time' to control it over the internet and use the produced audio in a song ;). Ok, back to a more serious note now. I'll start programming on a dedicated MBSID V2 editor and librarian then. Is there a preferred programming language? Maybe Java? Or C++? I think having an .exe executable program would be really nice. Or can I assume that everyone has Java installed? Greetings, Rutger Greetings, Rutger

Hi guys, I hadn't checked the forum for a couple of weeks because of moving to a new appartement, but I'm back on the forum now :). So to the point now: WOW! This polymode is amazing. Tonight I changed the lines in the code that I need for my hardware and recompiled and uploaded the HEX files. I've played with it for quite a while and I'm really deeply impressed. It's amazing what those SID's can do! I still haven't used the 8 Moog filters in this new polymode, but I assume that these will even add to the fatness of the sound. A more practical question by the way: is anyone currently working on a PC editor for the MBSID V2? If not, I'd be happy to start working on that. I myself would really like to have an easy patch/bank-manager as well as an editor (since I only have a simple control surface). Greetings, Rutger ps. Does anyone know if the MBSID V2 responds to bank messages? I think it would be nice. I can send those from my Korg Triton to my Yamaha S30 to select a certain bank and patch number. Maybe this would be cool for the MBSID V2 too? Or is that already implemented and did I miss something?

I can think of 2 alternatives: - Hold Select #1 while turning the knob. This seems logical because it's also the button that activates the menu (but in that case it's not being held). But it might be confusing. - Use the menu-button to change the rotationspeed and use the shift button to change Ensembles while turning the knob. I think I personally prefer the second one.... It seems to be a bit more logical that the button below the rotary encoder affects the behaviour of this encoder. The shift is also closer to the Ens item in the display... Greetings, Rutger

Amazing! That's a very nice approach to electronic drums! Rutger

I've created a PSU for my 8xSID MidiBox with 8 additional Moog filters. The schematic and some explanation can be found here: http://www.midibox.org/forum/index.php?topic=9236.0

I think you (and other people that gave their advice on the transformer) should take a look again at the link to the PSU kit. I noticed that the website mentions: Supply voltage: 18V AC / 200mA It also mentions the use 7812 and 7912 regulators. These regulators need at least a bit more (!) than 12V to do their job (that is: regulating the DC power to keep it around +12V and -12V). I think that using a 2x12V (this is the same as a 24V center tapped) transformer will not give you enough potential for a stable PSU. I'd rather go for a 2x15V (30V center tapped). If you have a hard time finding this one you could also use a 2x18V transformer but this will result in much more heat on your regulators. I would also recommend to buy a transformer that can deliver a bit more current than you actually need. This improves the performance of the transfomer. Greetings, Rutger ps. I found this site to be very usefull in PSU design issues: http://sound.westhost.com/power-supplies.htm

Very cool, those SSM's! I recently did repairs on an Ensoniq ESQ1 by the way. Very clearly it's the work of Robert Yannes again, just like the SID! I really like the sound and the implementation of the Operating System. Simple but very flexible. He also uses 8 CEM's controlled by a DAC. Greetings, Rutger

Hi TK, I understand completely. My reason for sharing my thoughts on the SuperPoly mode is not to put pressure on you but to keep the item open for discussion with other people. I just like to think about and discuss these design-related issues and I'm also curious about what other people think about it. I tried to point out what approach of the Poly-mode would be interesting for my use and I'm interested to hear about other people's opinions. So again, no pressure on you, TK! You already did an amazing job on the current V2 beta release! I'm even surprised that you call it 'Beta' ;) and I'm not at all concerned about taking the SID synth with me to a live gig, even with the Beta version running on it!! Greetings, Rutger ps. I'd be happy to supply you with a bunch of new patches! However, because of my hardware, most of them will require an external filter. Do you still have the CEM's or Moog filter attached to the AOUT of you MBSID V2? pps. I'll be moving to a new appartement in Nijmegen, Netherlands by the end of this month for a new job on Brain-Computer Interfaces (i.e. controlling a SID synth with your thoughts ;)). After I finished moving I'll install Java again and see if I can come up with a nice editor. I only have the plan B control surface so I'd like a good editor myself and I have experience with several bank managers and editors (i.e. SoundDiver, etc).

Oh, I almost forget. I'm really really looking forward to the Super Poly mode for the new V2. I recently had an email conversation with Wilba about it since it's interesting for almost anyone who's building the 8xSID midibox in some form. Some ideas I had on how this Super Poly mode could look like are: 1. The first 'generation' of the Super Poly mode should not nescessarily use the CAN-bus for all data communication (including all notes to the slaves). Instead the master core could send only enable/disable commands over the CAN-bus to the slaves that enables or disables the response of a certain SID to an incoming note event on the midi-input. This will keep down the load on the CAN bus and the midi-in wiring doesn't need to be changed. 2. Each core could have an enable 'SuperPoly' switch that automatically sets the midichannel of this core to the midichannel of the master core. The number of slave cores set to 'SuperPoly' automatically determine the number of voices available. 3. I believe that the most interesting forms of SuperPoly mode are 8-voice mono and 4-voice stereo. 6-voice mono with an additional monophonic sound on a different midichannel on the remaining core could also be interesting (for a bassline). Each voice would have 3 oscillators (1 voice per SID). That way you have a filter per voice. In the case of 4-voice stereo you could even keep the entire lead engine setup. In case of the 8-voice mono mode the PIC cpu power will probably not be enough to account for all LFO's, modulation, etc of the lead engine. That's just some of my thoughts. If I can help in any other way, please let me know. Greetings, Rutger

Ehm, almost ;) After some testing I discovered some anomalies in the sustain handling. When I press a note, press the pedal and release it again (while still holding the note with my finger) the envelope retriggers...while I believe it should not. I believe that somehow the software should keep track of note-off commands from the keyboard during pedal-hold. If a note off occurs and no new note-on command occurs the pedal can 'mute' the note when it's released. When the note is still played on the keyboard while the pedal is release the pedal action should NOT mute the note. Hope that this info helps on improving the pedal behaviour. Other than that, great work! At the moment I'm running experiments on the temperature stability of the filter. I've created a filter envelope on a lead sound that I want to go from 'just above audible cutoff' to completely open filter and see if the envelope stays the same over time and temperature.... I've omitted the temperature compensation of Rick Jansen's schematic to keep down costs and construction difficulty. My goal was to make this filter a bit more friendly for the average MidiBox-builder in the sence of costs and part availablilty through Reichelt.de. If all works well I'll share more detailed info on the filter with everyone. Greetings, Rutger

Why don't you give PCBEXPRESS a call? I'm sure they file their finished order. Greetings, Rutger

Hi, I just finished an 8xSID synth (+ 8 moog filters) and put it in an 19" enclosure. It's running on the new MBSID V2 beta 8 software since yesterday and I plan to use it for a couple of gigs with the band Autumn: www.autumn-band.com. I've been asked to replace their keyboardist (Jan Munnik) for a couple of gigs, so I've been working on the songs and sounds for the past few weeks and the SID synth seems to fit in nicely for some leads and fx. With my former band Orpheo (www.orpheo.nl) I've been playing on another synth that was a DIY project. It's a semi-modular analog synth (monophonic). So, yes, I think these DIY synths can be used for studio and live purposes. Greetings, Rutger

I just uploaded Beta 8 and the new sustain function is working very well! Rutger

Wow, TK, that's fast! Do you ever sleep? I'll try it tonight and see if it works in my setup. Greetings, Rutger

Very very cool! Greetings, Rutger

Haha, thank you both, TK and Wilba! I'll leave out the MIDI led on the frontpanel then! I don't need it anyway since my MOTU midi patch bay already has activity LEDS. I'm really looking forward to the more advanced CC options however! Especially the sustain (CC #64) parameter is very essential for me as a live musician, because I use it to play more parts with less fingers ;). For instance I hit a lowish note (drone-like sound) at the SID synth and hold it with the sustain pedal while playing other parts on different instruments over this drone. A 'default' assignment of the sustainpedal in the SID software would therefore be very nice! Kind regards, Rutger ps. TK, MBSID V2 is still kicking ass sound-wise ;)

Hi TK, I have a couple of (I hope simple) final questions: 1. Is there a way to assign CC controllers from my master keyboard to certain features in the SID synth? I only found a working way through the KNOB CC's, but my sustain pedal is not having any effect and the MdW source is not passing on the position of my modwheel. Is there a way to activate the sustain pedal (CC# 64) and the modwheel? 2. How can I set the MIDI TX/RX LED function to an output of J5? I already found that SR# 0 is the J5 connection, but I cannot find how I route the MIDI TX/RX LED functions to this output. Kind regards, Rutger

Hi guys, just another update. I've now tested all AOUT_LC modules and each of the 4 cores and everything works perfectly! I've made some big improvements on hum and digital noise problem by the way. When I took a closer look to my PSU I found that the -12V wasn't as clear as I expected after all. Some 100Hz (due to full wave rectifier), 1mV peak to peak, was still there, while it was absent at the +12V line. It appeared that the ground also carried this waveform, but only close to the PSU and even of different levels at different ground points in the PSU. I think that the PCB track resistance and path (-12V grouding being the farthest away) caused these strange differences in ground potential. The solution in this case was simple: an extra (very FAT) wire across the PSU (from ground to ground) to have some extra low resistance connection to the point where the whole system is grounded (center tap from transformer). The problem of extra hum when joining the earth and local ground is solved with this too! The last fix I made was increasing the gain of the opamp that goes into the Moog filter circuit and decreasing the gain of the output stage. Raising the signal level as early as possible (directly after the SID) improved the S/N ratio alot! A final fix (a very nice one, I think!) to the SID's own noise problem is to drop the Moog filter cutoff to below audible when the SID's not playing. This really makes a very nice and quite synth. I only have to modify all patches to do so, but I have to build patches anyway! Up next: designing the frontpanel and paying the Schaeffer-company too much for their overpriced but totaly hot frontpanels! I really have to say that I'm totaly amazed by all the work TK already put into the SID V2 design! And I'm really glad that I solved all the problems. The synth is now ready for stage! I'll probably be doing 4 shows with it in september and oktober! :). Kind regards, Rutger ps. Oh, before I go....I have one little question (quote: Columbo): - TK, did you take into account that some keyboardists like to pitch-bend up for about 2 octaves, keep the bender there for a while (while playing different notes) and that these notes will be out of tune when there's not compensation for the pitch scaling?

You're right! Sorry for the false alarm ;)

Hi guys (and girls), No, I did not. The V2A option is turned off. I've also set the AOUT_LC output channels for the V2A option to 0 (= off), in the setup asm file. Haha, thanks for the explanation! I'm already really really happy with the sound and the options so far. You've done an amazing job, TK! I've found a way to eliminate the noise a bit more. I found that part of the noise came from a capacitor in the op-amp integrator circuit in the output stage (which is not part of TK's design, of course ;D). The capacitors in this circuit are very sensitive to interference and I put one quite close to the on-board bankstick EEPROM's. Appearantly these can cause quite some interference... I've moved the capacitor, extending the leads with some extra wire, and that works quite well. The left channel of the output still has a bit of digital noise, but the S/N ratio has improved quite a bit. I hope it will be enough. Another solution would be to rebuild the output stage on a seperate board and mount it away from any other stuff. I plan to write some detailed info on the PSU and Moog filter designs, with schematics and maybe a PCB layout as well. The PSU has been tested up to full load of my circuit and is still holding very well, although it runs rather hot. I definitely don't want to touch it after the synth has been on for more than half an hour. Greetings, Rutger ps. Anyone have some spare 8580/6582? I'd be glad to exchange for some tested and known-to-be-working 6581's.

Hi TK, I have very good news! I have the AOUT_LC's working. In the design fase I wasn't aware of the abnormal connection between J6(Core) and J1(AOUT), so I just mapped the pins 1:1. Somehow this caused the AOUT_LC to put out rather random signals. However, I fixed the connection (had to break some of those nice 12mil traces on my PCB :'( and replace with a wire link) and went back to the original AOUT_LC driver. Now the output made much more sense. From this point I was able to rewrite the driver to output my 12/12/8 configuration. Today I recalculated the gain needed to reach a maximum of 10.67V output from the AOUT_LC's (I don't have trimmers, but fixed resistors). After this I made some adjustments to the CV control of the resonance and tuned the filters. Wow! Those filters really kick much more uhm...arsch...than the SID's internal ones (at least those of the 6581). Thank you Rick Jansen and Bob Moog! The only problem I still have is that there's too much digital noise coming through the outputs, but I'm not sure where it comes from. I kept the analog and digital supply lines seperated until the PSU and I have seperate analog and digital grounds. Wilba, did you have similar issues with your big PCB? Two points that could possible be bugs in the Beta 7 release: - The volume parameter in the CFG menu is NOT affecting the SID's volume (6581). - When I switch to another patch the 6581's give a loud click (not related to noise from the encoder itself). It really comes from the SID's audio output. The 8580 does not give this click. Kind regards, Rutger